Solar battery installation across South Carolina

What changed in South Carolina, and why older advice is wrong

Three things moved in sequence, and together they reset the arithmetic. One-for-one net metering closed to new applicants on 1 June 2021. Full-retail grandfathering for customers who applied before 16 May 2019 ran out on 31 December 2025. And the federal residential credit expired for systems placed in service on or after 1 January 2026.

The practical result is that payback in South Carolina is longer than the figures still published on national comparison sites, which mostly have not been updated. If you are working from an article that applies a 30% federal credit, the net cost it shows you is wrong by thousands of dollars. It is the first thing to check on anything you read, including a quote.

What did not change is the 25% South Carolina state credit on Form TC-38, capped at $3,500 in any one tax year and at 50% of your state liability, with a ten-year carry-forward. Because of that annual cap, most residential systems are claimed across two or three returns rather than recovered at once. Confirm your own eligibility with a tax professional.

None of this makes solar a bad decision here. It makes it a decision that has to be worked rather than assumed, and one where which utility bills you now matters more than it ever has.

Why storage got more valuable at exactly the moment solar got harder

When exported power was credited close to one-for-one, the grid was an almost perfect battery and a physical one was mostly about riding out storms. Now that utilities credit exports at a fraction of retail, a kilowatt-hour you store and use yourself is worth several times one you export. The same rate change that lengthened solar payback shortened the case for storage.

How strong that argument is depends on where you are. Duke territory has the widest gap between retail and export rates, which makes the economics clearest there. Where the gap is narrower, storage has less economic work to do and the resilience case has to carry more of the decision.

On the coast, resilience is separately compelling and largely independent of the arithmetic. Hurricane outages run for days rather than hours, and that is a different specification question from economic time-shifting.

When a generator is the better answer

Duration decides it. A battery has finite capacity and needs sun or grid to refill; a generator runs as long as it has fuel. If the realistic worst case in your area is a multi-day outage after a storm, a battery sized to match would be very expensive, and a generator’s fuel supply is the thing that actually matters.

If the realistic worst case is a few hours, a battery covers it comfortably and does useful economic work the rest of the year, which a generator does not. That is the trade in one sentence.

Some households sensibly have both: the battery working daily, the generator covering the tail risk. It is also the most expensive answer, so it should be a deliberate choice rather than a default. Each page below says plainly where a standby generator would be the better buy for that market.

How to use these pages

Start with your town rather than the state. Every page below is grouped by the utility that serves it, because that is the variable doing the most work, and a statewide average is a number that applies to nobody in particular.

Then check the assumption behind any figure you are comparing. Two quotes for a similar system can differ enormously on their twenty-five year totals purely because of what each assumed about export credits and rate escalation, and neither assumption is usually stated on the front page.

If your town is not listed, it is worth asking rather than assuming we do not cover it. We install statewide from a Daniel Island office, and the page list reflects where we have enough verified local detail to publish something useful rather than the limit of where we work.

What we need to give you a real number

Twelve months of electricity usage. Not one bill, twelve. A system sized from a summer peak is oversized for the year and one sized from a mild month disappoints every August, and neither error is visible until the system is on the roof. Twelve months also shows us the shape of your consumption across the day, which is what determines how much of your own production you will actually use rather than export.

Confirmation of who serves your meter, read off the bill rather than inferred from your address. In the Charleston metro especially, territory boundaries run between streets, and modelling the wrong provider produces a confident answer to the wrong question.

Some idea of your roof: its age, its covering, and whether anything has grown up around it since you moved in. Roof age is the detail that most often changes our recommendation, because installing over a roof with a few years left means paying to remove and reinstall the array later.

And your own horizon. A household planning to move within a few years is making a resale decision rather than a payback decision, and those are different questions with genuinely different answers. Telling us early saves everyone a survey.

With those four things we can give you figures rather than a projection built on averages. Without them, anyone quoting you a payback period is guessing with a straight face.

Common questions

Is a home battery worth it in South Carolina now?

The case improved at the start of 2026. Because utilities now credit exports at a fraction of retail, a kilowatt-hour you store and use yourself is worth several times one you export. Duke territory has the widest gap, so the economics are clearest there.

Battery or generator?

Duration decides it. A battery has finite capacity but does economic work year-round; a generator runs as long as it has fuel, which suits multi-day storm outages. On the coast, where outages run for days, a generator is often the better answer.

Can a battery power my whole house?

Not indefinitely, and air conditioning consumes a great deal of the available capacity in a Lowcountry summer. Which circuits are backed up is a design decision made in advance.

Do I need solar to have a battery?

No, though the economic argument is much stronger with it, since the value comes from storing your own generation rather than exporting it cheaply. Without solar the case is resilience alone.

Will a battery fix a shaded or undersized array?

No. Storage moves energy in time; it does not create it. If the array is the constraint, a battery adds cost without addressing it.